Identification card printers along with the aid of a computer are typically used to form identification cards by printing an image on a print receptive surface of a card substrate. The image generally includes a photograph and other information relating to the card holder, such as the card holder's name, employee number, and other information. Such identification cards are used for many purposes, such as driver's licenses, identification badges, etc.
The image that is to be printed on the surface of the card by the identification card printer is generally formed by combining textual and graphical portions received from host applications running on the computer or from other input devices such as keyboards, scanners, and digital cameras. Data relating to the formatted image is then provided to the identification card printer in the form of a print job. The identification card printer processes the print job by printing the image onto the print receptive surface of the card substrate.
Identification card printers generally employ a card holder containing a stack of the card substrates, a card transport mechanism, and a print mechanism. The card transport mechanism is generally configured to transport cards from the card holder to the print mechanism for printing. Thermal-based identification card printers employ a print mechanism having a thermal print ribbon having primary color dye panels and a thermal printhead. The thermal printhead heats the ribbon and causes dye on the color panels to be released and sublimate into the print receptive surface of the card substrate. Alternatively, the identification card printer can employ an ink jet printhead having a supply of ink.
Identification card printer designers are continuously striving to improve the quality of the image that is printed on the card substrate. The print quality is determined, in part, by the quality of the print mechanism and the print receptive surface of the card substrate. Additionally, the print of an image is limited to the cleanliness of the print receptive surface of the card substrate. Thus, the more the print receptive surface is contaminated by dust and debris, the lower the quality of the image that can be printed thereon.
Such contaminants can infiltrate identification card printers in many different ways. Dust can enter the identification card printer through vents and be circulated through the printer by cooling fans. Such contaminants can be attracted to the surfaces of the card substrates due to static charge. This is particularly problematic when, for example, the card holder of the identification card printer is not configured to fully enclose the stack of cards, but includes an opening to allow for easy loading and unloading of the cards. However, even when the card holder fully encloses the cards, there may be no guarantee that the cards enclosed therein are contaminate free. Jostling of the cards during transport could generate undesirable contaminants. Additionally, once the cards are ejected from the enclosed card holder, contaminants circulating through the identification card printer can be attracted to the print receptive surface of the card.